Two thin lenses of powers `2D` and `3D` are placed in contact. An object is placed at a distance of 30 cm from the combination The distance in cm of the image from the combination isA. 30B. 40C. 50D. 60

Two thin lenses of powers `2D` and `3D` are placed in contact. An obje

1.	Two thin lenses of powers `2D` and `3D` are placed in contact. An object is placed at a distance of 30 cm from the combination The distance in cm of the image from the combination isA. 30B. 40C. 50D. 60
Answer» Correct Answer - D `P=P_1+P_2=5D,F=(100)/(P)=(100)/(5)=20cm` `(1)/9v-(1)/(-30)=(1)/(20)` `(1)/(v)=(1)/(20)-(1)/(30)=(1)/(60)impliesv=60cm`

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Two thin lenses of powers `2D` and `3D` are placed in contact. An object is placed at a distance of 30 cm from the combination The distance in cm of the image from the combination isA. 30B. 40C. 50D. 60

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